Protector shield

ABSTRACT

A protective shield for the terminals of thermostats mounted on water heaters is disclosed. The shield is formed of heavy fish paper shaped to provide access to the thermostat controls while preventing accidental contact with the terminals and connecting leads. Mounting portions are provided on the shield for removably mounting the shield in place.

United States Patent Inventors Edward G. Them; [56] References Cited A lN 33218:! S. Deubel, both of Mansfield, Ohio UNITED STATES PATENTS 'ff15 1970 2,862,997 l2/l958 Veitch et al. 174/138 F Patented 7 1 3,435,1893/1969 Manecke 2l9/330X Assignee Therm-O-DIsc Incorporated PrimaryExaminer-C. L. Albritton Mansfield, Ohio Attorney-McNenny, F arrington,Pearne and Gordon PROTECTOR SHIELD ABSTRACT: A protective shield for theterminals of therl0 Claims, 5 Drawing Figs. mostats mounted on waterheaters is disclosed. The shield is U s 219 I328 formed of heavy fishpaper shaped to provide access to the F 219/336 thermostat controlswhile preventing accidental contact with Int Cl 1' 1 1/00 the terminalsand connecting leads. Mounting portions are i 952L330 provided on theshield forremovably mounting the shield in 31o-a12,321;174/s R, 138 r,66, 1

*v- I i (r \V f 5 e 1/-.'

' 22 f I 4/ 4a '1 Q 34 8 J3 I 8 3 {7 .56 J I J 1 I i 53 J6 A 1 PROTECTORSI-IIELD BACKGROUND OF THE INVENTION This invention relates generally tothermostatically controlled heaters and the like and more particularlyto a combination of a control thermostat assembly and a removableprotective shield which prevents accidental contact with electricallycharged terminals and the like.

PRIOR ART Automatic electric water heaters are provided withtemperature-sensing thermostats to control the operation of theresistance heaters. Generally, such water heaters include an inner tankin'which the water is heated and stored, thermal insulating materialaround such tank, and an outer casing en-. closing the tank and thermalinsulating material. Usually, the thermostat is mounted against theinner tank in temperature sensing relationship therewith. An accessopening is provided in the outer shell adjacent to the thermostat orthermostats which-is normally closed by a removable cover so that accesscan be obtained to the thermostat for adjusting of the operatingtemperature of the thermostat. In most instances, a highlimit thermostatof the manual reset type is also provided and access to such thermostatfor resetting is also provided through the opening in the outer shell.

The thermostats are normally connected to the heaters and to theelectrical supply by lead wires secured to terminals on the thermostats.Consequently, exposed wiring is located at a position substantiallyadjacent to the reset mechanism and the temperature-adjusting mechanism.Because the exposed wiring is adjacent to the'thermostat controlmechanisms, there is a possibility of accidental contact with theexposed and charged wiring when the user either resets the thermostatsor adjusts the operating temperatures thereof.

SUMMARY OF THE INVENTION The present invention is directed to acombination of a thermostat having operating controls and exposedterminals substantially adjacent thereto and a removable protectiveshield which limits access to the exposed wiring while providing accessfor the control of the thermostat. Such protective shield therefore,prevents accidental contact with the exposed wiring, but is removable topermit access thereto when the thermostat must be serviced or replaced.

The illustrated embodiments of this invention include a pair ofthermostats of the type used to control the operation of an automaticelectric water heater. One of the thermostats in the illustratedembodiment is a manual reset high-limit control thermostat and the otheris a temperature-controlling thermostat which is manually adjustable. Aprotective shield formed of heavy fish paper or the like, which isrelatively stiff but can be bent to a limited extent, is removablymounted on the thermostat in a position to prevent accidental contactwith the exposed terminals and connecting lead wires while stillproviding access to the two thermostats for resetting or temperature ad-BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary perspectiveview of a typical electric hot water heater illustrating the mounting ofthermostats thereon and the connection of the thermostats to the heaterelements;

FIG. 2 is a view similar to FIG. I with the protective shield, inaccordance with this invention, in place;

FIG. 2a is an enlarged view of the protective shield beforeinstallation;

FIG. 3 is a fragmentary perspective view of another typical installationof a thermostat and heaters on an electric hot water tank with anotherembodiment of a protective shield, in accordance with this invention,mounted thereon; and

FIG. 3a is an enlarged view of the protective shield illustrated in FIG.3.

DETAILED. DESCRIPTION OF THE DRAWINGS Referring to FIGS. 1 through 3, atypical electric water heater includes an inner tank l0 surrounded bythermal insulation 11 which is, in turn, enclosed within an outer case12. An access opening 28 is provided in the outer case. Mounted on theinner tank 10, within the access opening, are one or moreresistance-type electric heaters 13 which operate to heat the waterwithin the tank 10 when supplied with electrical power. Automatictemperature control is provided by a pair of thermostats l6 and 17. Inthe illustrated embodiment, the upper thermostat 16 is a high-limitthermostat of the manual reset type, and the lower thermostat 17 is thetemperaturecontrolling thermostat. The high-limit thermostat 16 does notoperate under normal conditions, but opens to shut off the heaters 13whenever excessive temperatures are encountered. Such thermostat is ofthe manual reset type wherein the thermostat switch remains open untilthe thermostat is manually reset by pressing the reset button 18.

The lower thermostat I7 is the thermostat which controls the operationof heaters 13 in normal operation of the water heater. Such thermostatis manually adjustable to a desired temperature by turning an adjustmentelement 19. Once adjusted, the thermostat turns the heaters 13 on andoff to maintain the desired water temperature. Thermostats of the typeillustrated are disclosed in the US. Pat. No. Des. 203,945.

Each of the thermostats is provided with terminals 21 for connection topower leads. These terminals are in the forward faces of the thermostatsso that they are easily accessible for connecting and disconnecting theleads during installation and servicing of the system. However, suchterminals, since they are adjacentto the reset button 18 and theadjusting element 19, are susceptible to accidental contact when thethermostat 16 is reset or the thermostat I7 is adjusted.

In the illustrated embodiment, the two leads 22 and 23 connect thehigh-limit thermostat 16 to a source of power. The leads 24 and 26connect the thermostat assembly to the terminals 27 of the heaters 13;Aremovable cover (not illustrated) is normally mounted over the opening28 and is removed when access is required to the thermostats or theheaters.

FIG. 2 illustrates the same electric water heater with a protectiveshield 31 in place. The protective shield is preferably formed of arelatively stiff sheet material which is electrically insulating incharacter such as l/32-inch-thick fish paper. Such paper is sufficientlyflexible, however, to permit the shield to be slipped into place and tobe removed when necessary for servicing of the thermostats or heaters.

The shield includes a main body portion 32 formed with an opening 33therein proportioned to closely fit around the reset projection 34.Also, the main body portion is also formed with an opening 36 positionedover the adjusting element 19 and providing access thereto when theshield is in place. A laterally projecting portion 37 is proportioned tocover the heaters 13 and extends at its end 38 under the outer case 12adjacent to the opening 28. Because of the cylindrical shape of the tank10 and case 12, the lateral projection 37 tends to assume a curved shapewhen the shield is mounted in position.

In order to secure the shield to the thermostats l6 and 17, the shieldis formed with spaced mounting portions 41 and 42. The mounting portion41 is formed by two cuts 43 and 44 and is provided with a hinge line 46so that it can bend back from the plane of the shield. The hinge line isprovided by scoring the shield material with a shallow cut partiallythrough the material from the forward face. The cut 43 is shaped so thatthe mounting portion 41 provides a lateral extension 47 which fitsbehind the lead 22 and engages the backside thereof, as illustrated inFIG. 2. Adjacent to the mounting portion 41 is a projection 48 whichextends up behind the outer shell 12.

The lower mounting portion. 42 is formed along the lower edge of theopening 36. This mounting portion has a semicircular recess 51 shaped tofit against the shaft 52 on which the adjusting element 19 is mounted.Projections 53 and 54 are provided on each side of the groove 51 toextend behind the adjusting element 19 to hold the lower section of theshield substantially against the adjacent surface 56 of the thermostat17. A notch 57 is provided to receive the stop pin 58.

The two mounting portions 41 and 42, because they engage rearwardlyfacing surfaces on this thermostat assembly, securely hold the shield 31against the forward face of the thermostats. These portions, incooperation with the engagement between the edge of the opening 33 andthe reset projection 34, provide exact proper location of the shieldwith respect to the thermostats. Consequently, access to the resetbutton 18 and the adjustment element 19 is insured.

The shield is installed by inserting the projection 37 behind the outercase 12 with the main portion 31 slightly below the ultimate mountingposition. The shield is moved upwardly while holding the mountingportion 42 back against the thermostat until the projections 53 and 54are properly positioned behind the adjusting element 19. The projection48 is preferably positioned behind the outer case 12 by this movement.As soon as the lower mounting portion 42 properly engages the adjustingelement, the opening 33 is in proper registry to slip down over thereset projection 34. The upper mounting portion is then bent back andpositioned behind the lead wire22 to complete the mounting of theshield. When the shield is in position, accidental contact with any ofthe terminals is prevented. However, in the event that servicing of theheaters or the thermostats is required, the shield is easily removed toprovide full access. After the servicing is completed, the shield isreplaced in the same manner as it is originally installed. The materialforming the shield should be sufficiently heat resistant and resistantto moisture or the like to prevent its deterioration in use;

FIGS. 3 and 3a illustrate a second embodiment of this invention whereinthe physical arrangement of the mounting of the thermostats and theheaters on the water heater is different than illustrated in FIG. 1. inthis embodiment, similar reference numerals will be utilized todesignate similar parts with a prime added to indicate that reference isbeing made to the second embodiment. The high-limit thermostat 16 andthe temperature controlling thermostat 17' are again mounted within anaccess opening 28 in the outer case 12' of the water heater. in thisinstance, however. the electric heaters 13' are mounted on the innertank directly below the thermostats. The protective shield 31' is againformed with an upper mounting portion 41 having the same shape as themounting portion in the first embodiment, and a lower mounting portion42' proportioned to fit behind the adjusting element 19'. The mountingof the shield against the thermostats 16 and 17 is exactly the same asin the first embodiment. However, in this instance, the shield isprovided with a downwardly extending projection 61' which extends overthe heaters 13' and under the outer case 12 at its lower end. The upperprojection 48' also extends up under the outer case 12'.

The principal difference between this embodiment and the firstembodiment is that the downwardly projection portion 61' is utilized tocover the heaters 13' and the leads connected thereto, instead of thelateral projecting portion 37.

With a protective shield incorporating the present invention a low-costdevice is provided which is easily installed to protect the user againstaccidental contact with terminals and connected leads while providingaccess for operating the thermostats. The protective shield, however, iseasily removed when access to the thermostats or heaters is required forservicing. After servicing, the shield can be replaced. Since the shieldis accurately located with respect to the thermostats, the access forcontrolling the operation of the thermostats is insured.

in both embodiments the reset button projection 34 provides opposedsurfaces which are engaged to accurately locate the upper end of theshield. Similarly, the projections 53 and 54 and the notch 57 engageopposite sides of the shaft 52 and the pin 57, respectively, andcooperate with the reset button 34 to position the lower end of theshield. Because the notch 57 extends below the lower edge of the opening36, the shield will not fit into place unless it is properly alignedwith the thermostat assembly.

Although the shield incorporating this invention is illustrated in usein a typical electric water heater, it is equally useful for protectingthe terminals of thermostats or the like in other thermostaticallycontrolled, temperature changing devices.

Although preferred embodiments of this invention are illustrated, it isto be understood that various modifications and rearrangements of partsmay be resorted to without departing from the scope of the inventiondisclosed and claimed herein.

What is claimed is:

1. A temperature-controlling system comprising a device havingelectrically controlled temperature changing means, thermostat meansmounted on said device having a forward face, control means on saidforward face, said thermostat means also including terminal meansaccessible from said forward face and lead wires connecting some of saidterminals to said temperature changing means for controlling theoperation thereof, said thermostat means providing at least two spacedsurfaces facing in a direction opposite said forward face, and aprotective shield removably mounted against said forward face formed ofa relatively stiff bendable electrical insulating material, said shieldproviding; a portion covering said terminals and the connections thereofto said lead wire for limiting access thereto, opening means providingaccess to said control means, and mounting portions engaging said spacedsurfaces operating to secure said shield in position against saidforward face.

2. A temperature-controlling system as set forth in claim 1 wherein saidthermostat means provides opposed surfaces extending substantiallynormal to said forward face, and said shield engages said opposedsurfaces to provide location thereof with respect to said forward face.

' 3. A temperature-controlling system as set forth in claim 2 wherein atleast one of said operating means is located on a boss projecting fromsaid forward face, said boss providing said opposed surfaces, saidopening means closely fitting said boss and locating said shield withrespect to said forward face.

4. A temperature-controlling system as set forth in claim 3 wherein atleast one of said spaced surfaces is provided by a lead wire.

5. A temperature-controlling system as set forth in claim 4 wherein saiddevice is an electric water heater, said temperature changing means isan electric resistance heater controlled by said thermostat meanslocated substantially adjacent to said thermostat means, said resistanceheater having a heater terminal connected to a lead wire, and saidshield provides an extension extending over said heater terminal andlimiting access thereto.

6. A temperature-controlling system as set forth in claim 5 wherein saidwater heater is provided with an outer shell, and the end of saidextension extends under said outer shell.

7. A temperature-controlling system as set forth in claim 6 wherein saidthermostat means includes an adjustable thermostat and a manual resethigh-limit thermostat, said control means includes temperature adjustingmeans on said adjustable thermostat and reset means on said high-limitthermostat spaced from said adjusting means, and said opening meansincludes separate openings for said adjusting means and said resetmeans.

8. A temperature-controlling system as set forth in claim 7 wherein saidadjusting means provides another of said spaced surfaces.

tension extending over said heater terminal and limiting access thereto.

10. A temperature-controlling system as set forth in claim 9 whereinsaid water heater is provided with an outer shell, and the end of saidextension extends under said outer shell.

ll 'l i

1. A temperature-controlling system comprising a device havingelectrically controlled temperature changing means, thermostat meansmounted on said device having a forward face, control means on saidforward face, said thermostat means also including terminal meansaccessible from said forward face and lead wires connecting some of saidterminals to said temperature changing means for controlling theoperation thereof, said thermostat means providing at least two spacedsurfaces facing in a direction opposite said forward face, and aprotective shield removably mounted against said forward face formed ofa relatively stiff bendable electrical insulating material, said shieldproviding; a portion covering said terminals and the connections thereofto said lead wire for limiting access thereto, opening means providingaccess to said control means, and mounting portions engaging said spacedsurfaces operating to secure said shield in position against saidforward face.
 2. A temperature-controlling system as set forth in claim1 wherein said thermostat means provides opposed surfaces extendingsubstantially normal to said forward face, and said shield engages saidopposed surfaces to provide location thereof with respect to saidforward face.
 3. A temperature-controlling system as set forth in claim2 wherein at least one of said operating means is located on a bossprojecting from said forward face, said boss providing said opposedsurfaces, said opening means closely fitting said boss and loCating saidshield with respect to said forward face.
 4. A temperature-controllingsystem as set forth in claim 3 wherein at least one of said spacedsurfaces is provided by a lead wire.
 5. A temperature-controlling systemas set forth in claim 4 wherein said device is an electric water heater,said temperature changing means is an electric resistance heatercontrolled by said thermostat means located substantially adjacent tosaid thermostat means, said resistance heater having a heater terminalconnected to a lead wire, and said shield provides an extensionextending over said heater terminal and limiting access thereto.
 6. Atemperature-controlling system as set forth in claim 5 wherein saidwater heater is provided with an outer shell, and the end of saidextension extends under said outer shell.
 7. A temperature-controllingsystem as set forth in claim 6 wherein said thermostat means includes anadjustable thermostat and a manual reset high-limit thermostat, saidcontrol means includes temperature adjusting means on said adjustablethermostat and reset means on said high-limit thermostat spaced fromsaid adjusting means, and said opening means includes separate openingsfor said adjusting means and said reset means.
 8. Atemperature-controlling system as set forth in claim 7 wherein saidadjusting means provides another of said spaced surfaces.
 9. Atemperature-controlling system as set forth in claim 1 wherein saiddevice is an electric water heater, said temperature changing means isan electric resistance heater controlled by said thermostat meanslocated substantially adjacent to said thermostat means, said resistanceheater having a heater terminal connected to a lead wire, said shieldproviding an extension extending over said heater terminal and limitingaccess thereto.
 10. A temperature-controlling system as set forth inclaim 9 wherein said water heater is provided with an outer shell, andthe end of said extension extends under said outer shell.